Null,null#: {keyword}) Union All Select

Force a "True" result to log in without a password.

The # character (used in MySQL/MariaDB) comments out the rest of the legitimate query, preventing syntax errors from trailing code [3]. 3. Potential Risk An attacker successfully using this technique can: {KEYWORD}) UNION ALL SELECT NULL,NULL#

Implement parameterized queries (e.g., using PDO in PHP or PreparedStatement in Java). This ensures the database treats the input as text, not executable code [4]. Force a "True" result to log in without a password

Ensure the database user account has the minimum permissions necessary, preventing access to system-level tables [4]. preventing access to system-level tables [4].